Heavy Cotton Duck Dyeing Process Control and Levelness Optimization
Heavy cotton duck dyeing requires progressive electrolyte dosing, high-pressure liquor penetration, and strict tension control to eliminate surface ring-dyeing.
Tensile Degradation
Strength Reduction
Permanent loss of the load-bearing capacity in a textile material occurs when thermal and chemical stresses break the molecular chains of the constituent fibres. Evidence of tensile degradation is usually found after aggressive bleaching and curing or repeated recycling processes. Structural weakening reduces the service life of the garment and increases the risk of tearing during use.
Chemical Cause
Over-exposure to hydrogen peroxide or the use of strong acids on cellulosic fibres often leads to significant damage. These chemicals oxidize the glucose units in the cellulose, creating weak points that snap under tension. Monitoring the pH and the concentration of catalysts is a standard practice to prevent this type of hidden damage.
Measurement Protocol
Testing involves pulling a strip of fabric until it breaks and comparing the results to an untreated control sample. Standard methods like iso 13934 provide a reliable way to quantify the percentage of strength lost through tensile degradation during a specific production step. A loss exceeding ten percent is often grounds for an immediate investigation into the process parameters.
Structural Consequence
Thinning of the fibre walls and a decrease in the degree of polymerization are the underlying physical changes. These effects are irreversible and cannot be corrected by adding softeners.